1. Field of the Invention
The present invention relates to a storage controller, a storage system, and a storage controller control method.
2. Description of the Related Art
For example, government agencies, private companies and educational institutions handle large amounts of various types of data, and use relatively large-scale storage systems to manage this data. These storage systems comprise at least one storage controller. A storage controller, for example, comprises large numbers of storage devices, and can provide storage areas on the basis of RAID (Redundant Array of Inexpensive Disks). At least one logical device (also called logical volume) is created on the physical storage area provided by a group of storage devices. The writing and reading of data is carried out by a host computer (hereinafter, “host”) issuing a write command or a read command to a logical device.
The storage controller is connected to a large number of hosts, and respectively provides volumes to the hosts. Various data utilized by the hosts are stored in the respective volumes. Accordingly, methods for checking inside a storage controller to determine whether or not the data in the volumes has been infected with a computer virus, and for removing a detected computer virus have been proposed (Japanese Laid-open Patent Nos. 2004-46435, 2007-58346, and 2007-94803).
Furthermore, a technique for remote copying data from a storage controller at a primary site to a storage controller at a secondary site is also known (Japanese Patent Laid-open No. 2005-18506).
In the prior art, an entire secondary volume, which, together with a primary volume creates a copy-pair, is checked for computer viruses. Therefore, checking for computer viruses takes time, and increases the load placed on the controller. Further, since a backup process is carried out after the virus check of the entire secondary volume has ended, from the perspective of the host, backup also takes a long time.